/*
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 *
 * This software is open source.
 * See the bottom of this file for the licence.
 */

package com.googlecode.bluetools.dom4j.tree;

import java.io.IOException;
import java.io.Serializable;
import java.io.Writer;
import java.util.List;

import com.googlecode.bluetools.dom4j.Document;
import com.googlecode.bluetools.dom4j.DocumentFactory;
import com.googlecode.bluetools.dom4j.Element;
import com.googlecode.bluetools.dom4j.ILocatable;
import com.googlecode.bluetools.dom4j.Location;
import com.googlecode.bluetools.dom4j.Node;
import com.googlecode.bluetools.dom4j.NodeFilter;
import com.googlecode.bluetools.dom4j.XPath;
import com.googlecode.bluetools.dom4j.rule.Pattern;

/**
 * <p>
 * <code>AbstractNode</code> is an abstract base class for tree implementors to use for implementation inheritence.
 * </p>
 * 
 * @author <a href="mailto:james.strachan@metastuff.com">James Strachan </a>
 * @version $Revision: 1.1 $
 */
public abstract class AbstractNode implements Node, Cloneable, Serializable, ILocatable {
	protected static final String[] NODE_TYPE_NAMES = {
			"Node",
			"Element",
			"Attribute",
			"Text",
			"CDATA",
			"Entity",
			"Entity",
			"ProcessingInstruction",
			"Comment",
			"Document",
			"DocumentType",
			"DocumentFragment",
			"Notation",
			"Namespace",
			"Unknown"
	};

	/** The <code>DocumentFactory</code> instance used by default */
	private static final DocumentFactory DOCUMENT_FACTORY = DocumentFactory.getInstance();

	public AbstractNode() {
	}

	public short getNodeType() {
		return UNKNOWN_NODE;
	}

	public String getNodeTypeName() {
		int type = getNodeType();

		if ((type < 0) || (type >= NODE_TYPE_NAMES.length)) {
			return "Unknown";
		}

		return NODE_TYPE_NAMES[type];
	}

	public Document getDocument() {
		Element element = getParent();

		return (element != null) ? element.getDocument() : null;
	}

	public void setDocument(Document document) {
	}

	public Element getParent() {
		return null;
	}

	public void setParent(Element parent) {
	}

	public boolean supportsParent() {
		return false;
	}

	public boolean isReadOnly() {
		return true;
	}

	public boolean hasContent() {
		return false;
	}

	public String getPath() {
		return getPath(null);
	}

	public String getUniquePath() {
		return getUniquePath(null);
	}

	public Object clone() {
		if (isReadOnly()) {
			return this;
		}
		else {
			try {
				Node answer = (Node) super.clone();
				answer.setParent(null);
				answer.setDocument(null);

				return answer;
			}
			catch (CloneNotSupportedException e) {
				// should never happen
				throw new RuntimeException("This should never happen. Caught: " + e);
			}
		}
	}

	public Node detach() {
		Element parent = getParent();

		if (parent != null) {
			parent.remove(this);
		}
		else {
			Document document = getDocument();

			if (document != null) {
				document.remove(this);
			}
		}

		setParent(null);
		setDocument(null);

		return this;
	}

	public String getName() {
		return null;
	}

	public void setName(String name) {
		throw new UnsupportedOperationException("This node cannot be modified");
	}

	public String getText() {
		return null;
	}

	public String getStringValue() {
		return getText();
	}

	public void setText(String text) {
		throw new UnsupportedOperationException("This node cannot be modified");
	}

	public void write(Writer writer) throws IOException {
		writer.write(asXML());
	}

	// XPath methods
	public Object selectObject(String xpathExpression) {
		XPath xpath = createXPath(xpathExpression);

		return xpath.evaluate(this);
	}

	public List selectNodes(String xpathExpression) {
		XPath xpath = createXPath(xpathExpression);

		return xpath.selectNodes(this);
	}

	public List selectNodes(String xpathExpression, String comparisonXPathExpression) {
		return selectNodes(xpathExpression, comparisonXPathExpression, false);
	}

	public List selectNodes(String xpathExpression, String comparisonXPathExpression, boolean removeDuplicates) {
		XPath xpath = createXPath(xpathExpression);
		XPath sortBy = createXPath(comparisonXPathExpression);

		return xpath.selectNodes(this, sortBy, removeDuplicates);
	}

	public Node selectSingleNode(String xpathExpression) {
		XPath xpath = createXPath(xpathExpression);

		return xpath.selectSingleNode(this);
	}

	public String valueOf(String xpathExpression) {
		XPath xpath = createXPath(xpathExpression);

		return xpath.valueOf(this);
	}

	public Number numberValueOf(String xpathExpression) {
		XPath xpath = createXPath(xpathExpression);

		return xpath.numberValueOf(this);
	}

	public boolean matches(String patternText) {
		NodeFilter filter = createXPathFilter(patternText);

		return filter.matches(this);
	}

	public XPath createXPath(String xpathExpression) {
		return getDocumentFactory().createXPath(xpathExpression);
	}

	public NodeFilter createXPathFilter(String patternText) {
		return getDocumentFactory().createXPathFilter(patternText);
	}

	public Pattern createPattern(String patternText) {
		return getDocumentFactory().createPattern(patternText);
	}

	public Node asXPathResult(Element parent) {
		if (supportsParent()) {
			return this;
		}

		return createXPathResult(parent);
	}

	protected DocumentFactory getDocumentFactory() {
		return DOCUMENT_FACTORY;
	}

	protected Node createXPathResult(Element parent) {
		throw new RuntimeException("asXPathResult() not yet implemented fully " + "for: " + this);
	}

	//
	// methods for <code>ILocatable</code>
	//

	private Location startLocation;
	private Location endLocation;

	public Location getStartLocation() {
		return startLocation;
	}

	public void setStartLocation(Location startLocation) {
		this.startLocation = startLocation;
	}

	public Location getEndLocation() {
		return endLocation;
	}

	public void setEndLocation(Location endLocation) {
		this.endLocation = endLocation;
	}
}

/*
 * Redistribution and use of this software and associated documentation ("Software"), with or without modification, are
 * permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain copyright statements and notices. Redistributions must also contain a
 * copy of this document.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
 * following disclaimer in the documentation and/or other materials provided with the distribution.
 * 
 * 3. The name "DOM4J" must not be used to endorse or promote products derived from this Software without prior written
 * permission of MetaStuff, Ltd. For written permission, please contact dom4j-info@metastuff.com.
 * 
 * 4. Products derived from this Software may not be called "DOM4J" nor may "DOM4J" appear in their names without prior
 * written permission of MetaStuff, Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
 * 
 * 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
 * 
 * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 */
